Method for imparting waved finish to textile fabrics



E. W. LAWRENCE Oct. 23, 1956 METHOD FOR IMPARTING WAVED FINISH TOTEXTILE FABRICS 2 Sheets-Sheet 1 Filed March 24, 1954 IN V EN TOR.

Oct. 23, 1956 I E. w. LAWRENCE METHOD FOR IMPARTING WAVED FINISH TOTEXTILE FABRICS Filed March 24, 1954 2 Sheets-Sheet 2 INVENTOR. W W. WBY nited States Patent METHOD FOR llVIPARTING WAVED FINISH TO TEXTILEFABRICS Edward W. Lawrence, Johnston, R. L, assignor to Cranston PrintWorks Company, Cranston, R. L, a corporation of Rhode Island ApplicationMarch 24, 1954, Serial No. 418,425

3 Claims. (Cl. 117-11) This invention relates to the treatment oftextile fabrics and more particularly to a novel method for imparting tosaid fabrics a waved or rippled configuration resistant to washing, thesame being broadly included in the term finish, and to the novel productthereof.

Heretofore, waved finishes have been produced in textile fabrics bymeans of an embossing calender. Such method, however, required the useof an engraved metal cylinder which was geared and fitted together witha softer roll having a surface of wool, cotton, paper, or the like tocooperate with the engraved roll to produce embossed waves or ripples ina textile fabric passed therebetween. Although the end product of suchmethod was generally satisfactory, the method was an expensive one tocarry out, since not only was the required mechanism expensive,primarilybecause of the specially engraved roller required, but alsobecause it operated at a comparatively slow speed of the order of to 20yards per minute.

I have discovered that a unique waved or rippled finish resistant towashing may be produced in textile fabrics by the employment, in acertain novel modified manner, of a well-known type of textile finishingmachine already in use in many textile finishing plants for an entirelyunrelated purpose. More specifically, I have found that a conventionalcompressive shrinking machine, basically unchanged, may be adjusted andoperated in a novel manner to produce uniformly distributed,substantially parallel, somewhat discontinuous, rounded waves or ripplesgenerally perpendicular in direction to the warp yarns of a fabricpassed through such machine, such result being all the more unexpectedin View of the many years use in the textile finishing industry ofcompressive shrinking machines, without any realization of thepossibility of so operating them continuously to produce alongitudinally extended sheet of a novel textile fabric having anattractive waved or rippled configuration or finish somewhat similar tothat produced by the usual embossing, yet having its own uniquecharacteristics.

It is a particular feature of the method of my invention that it may hecarried out at the usual speeds of a compressive shrinking machine,which speeds are very much higher than with the heretofore knownembossing method described above.

It is a further feature of my invention that it may be carried out on aconventional compressive shrinking machine without radical mechanicalmodifications thereto so that such machine may be readily usedalternatively for compressive shrinking or for providing a waved orrippled finish according to my invention, respectively, depending uponthe adjustment and relationship of certain parts of the machine.

To explain still further features of the novel method as well as thewaved or rippled fabric of my invention, reference is now made to thefollowing detailed description of a preferred embodiment thereoftogether with the accompanying drawings, wherein in Fig. l is shown asomewhat diagrammatic view of the complete apparatus adapted to carryout my novel method, and in Fig. 2 is shown a diagrammatic isometricview of a novel textile fabric having a waved or rippled finish impartedby the method of my invention.

Referring now to Fig. l, the novel method of my invention comprisessupplying a continuous web of textile fabric F from a roll (not shown)preferably first to a friction calender having a heated upper roll 12and a heated lower roll 14 in frictional pressure contact with oneanother to provide a smooth glazed calendered surface finish on saidfabric. The fabric is then passed through a tank 16 containing asuitable resin-forming liquid mixture or solution 18 to impregnate thefabric with resin-forming components adapted to be heat-hardened tomaintain the finish of the fabric so that it will be resistant towashing as well as to ordinary wear. I prefer that the resin-formingsolution 18 contain a thermosetting type of resin essentially monomericin form, although partially polymerized resins may also be used. Also, Iprefer that the fabric be somewhat dried after impregnating, preferablyto about 5% to 15% moisture content, although not snfiicientlypermanently to harden or otherwise set the resin for reasons hereinafterappear ing. Typical of suitable resins which may be used are phenolformaldehyde, urea formaldehyde, melamine formaldehyde, and modifiedurea formaldehyde.

The impregnated fabric is then passed to a compressive shrinkingmachine, it being essential in the case of a thermo-setting resin thatthe resin-forming components in the fabric do not react to form ahardened resin before the configuration of the fabric is altered by suchmachine operated according to my invention as hereinafter explained,since if such occurs the ripples or waves formed will not beresistant'to washing. However, it may be desirable in some instances topartially set the resin. This problem will not arise with certain typesof thermoplastic resins, since the heat supplied to the fabric in thecompressive shrinking machine can be made sufficient to pro-soften suchresins for wrinkling.

The compressive shrinking machine itself is well known in the textilefinishing art and includes a rotatably mounted normally heated drum 2%)having a relatively thick blanket 22 forming a continuous web around amajor portion of its periphery, said blanket being supported and fedinto contact with said drum by an infeed roll 24 of relatively smalldiameter, the return flight of said blanket out of contact with saiddrum being supported by a number of supporting rolls 26. Typically, drum20 may have a diameter of about 5 feet and infeed roll 24 of about 2 to4 inches. The infeed roll 24 is provided with a heated curved shoe 28cooperating therewith to press the blanket 22 and fabric F by confiningthem therebetween and feed them to the heated drum 20, the outer surfaceof said relatively thick blanket being stretched by reason of the lank22 bending around the small diameter of infeed roll 24, and the infeedsheet of fabric being led onto said stretched surface of said blanket.

Although in the normal use of a compressive shrinking machine, the pointof shoe 28 is arranged to be almost in contact with the peripheralsurface of drum 20, with the infeed roll 24 as close to said surface asthe thickness of blanket 22 will permit, according to my invention, Ispace the shoe 28 and preferably also the infeed roll 24 a substantial,although limited, distance from the said surface of drum 25 That is, thepoint of shoe 28 is spaced a limited distance, say about .010 to .125inch, from the surface of drum 20 so that a limited length of saidfabric in progressively passing from contact with shoe 28 at its pointis released and remains substantially unconfined for a limited distancebefore it is again confined between the surface of drum 20 and blanket22. Also, the infeed roll 24 is preferably spaced from said surface at adistance of about .010 to .100

inch greater than required by the thickness of the movable blanket 22upon which the fabric is carried and by the fabric itself.

Thus, since the fabric contacting surface of blanket 22 in effectcontracts on passing between contact with the curved surface of shoe 28and contact with the oppositely curved surface of drum 20, the fabriccarried on said surface being substantially unconfined for a limiteddistance between shoe 28 and drum 20 and being fed toward said drum at aspeed about 2% to 6% greater than the peripheral speed thereof, willitself contract about 2% to 6% to form surprisingly uniformlydistributed, substantially parallel, rounded but discontinuous waves orripples generally perpendicular to the warp yarns of the fabric, asshown in Fig. 2. Furthermore, such wrinkles, once so formed, arestrangely enough not pressed fiat by reason of again being confinedbetween blanket 22 and drum 20, even though the resinous material hasnot yet been hardened, and they remain substantially similar inappearance even after hardening,

As the rippled or waved fabric F passes around the heated drum 20 it isdried and the resinous material therein is preferably at least partiallyhardened to aid in maintaining it in waved form, although I have foundthat with the conventional compressive shrinking machine it is difficultto achieve complete hardening without unduly slowing down the speed ofthe machine with consequent loss of production, since such machine maybe operated at its usual speed of about 50-70 feet per minute. Hence, Iprefer to take the fabric from drum 20 over suitable fabric supportingrolls 30 to a fabric take-up roll (not shown) and to complete thehardening process by the use of a conventional air dryer (not shown) inwhich the resin hardening is completed by heat hardening at atemperature of about, say, 300 F. for 5 minutes, to make the wavedfabric resistant to Washing.

The following will serve as typical examples of the practice of my novelmethod, although it will be understood that my invention is by no meanslimited thereto:

Example I A bleached 39 80 x 80 4.00 cotton cloth which had been dyed anapthol navy blue was impregnated with a solution of 6%% ethylene ureaformaldehyde, 2 /2% cationic softener, and 1 /2% organic acid catalyst.The cloth was then dried to ll2% moisture, run through a compressiveshrinking machine with a drum heated to about 300 F. and a 2%" infeedroll at a speed of 50-70 yards per minute, to form the ripples or waves,the shoe being heated to about 350 F. and with its point spaced about.070" from the drum surface and the infeed roll being spaced about .020"from the drum surface in addition to the thickness of the blanket plusthat of the fabric to leave an unconfined length of fabric, the speed ofthe infed cloth being about 5% higher than that of the peripheral speedof the drum to give a contraction of the cloth of about 5%. Afterpassing through composed in whole or in part of thermoplastic fibersaccording to the method of my invention, for example on fibers such asnylon, Dacron, and Orlon, since fabrics composed of such thermoplasticmaterials can be softened or otherwise modified by heat to set them in adesired shape or form which will be permanent unless the originalsetting temperature is again reached. Therefore, by running fabricscontaining thermoplastic fibers through a compressive shrinking machineat a temperature high enough to soften the resin, it is possible toobtain a permanently rippled or waved finish by the action of the heatedshoe 28 to soften the resin, which may then be hardened by a suitablylow temperature of drum 20. Likewise, a fabric modified by theapplication of thermoplastic resins may be similarly treated to providea waved or rippled finish.

The following examples will serve to illustrate the method of myinvention as applied to thermoplastic fibers.

Example 111 A filament nylon 152 x 100 fabric was run through acompressive shrinking machine as described above, having an infeed roll2% in diamter, feeding the nylon fabric at a speed of about 5% higherthan the peripheral speed of the drum, such machine being operated withits shoe at a temperature of 350 F. and its drum at 300 F., and with anunconfined fabric length, as described in Example 1. The resulting clothhad a series of small waves or ripples about A -Ma" across essentiallyperpendicular to the warp yarns of the fabric.

Example IV A spun Dacron 58 x 48 fabric was run as in Example III. Theresulting cloth had a series of ripples in the cloth about fii-Mi"across and essentially perpendicular to the warp direction of the cloth.

Thus it will be seen that I have provided a novel method forcontinuously producing in an extended sheet of textile fabric closelyadjacent waves or ripples uniformly distributed throughout the extent ofsaid sheet, such waves or ripples being substantially similar toembossed waves or ripples. Various modifications of my novel methodwithin the spirit of my invention and the scope of the appended claimswill occur to those skilled in the art.

I claim:

1. A method of finishing a continuous sheet of textile fabric to providesubstantially parallel and uniform waves therein generally perpendicularto the warp yarns of said said machine, the resin was cured 5 minutes at290 Example 11 A bleached 39" 80 x 80 4.00 cotton cloth which had beendyed a napthol navy blue was given a high luster by running on afriction glazing calender at 400 F. The sample was then run as describedin Example I. The finished cloth had a series of ripples or waves aboutVet- A across which were substantially parallel to the filling, with anall-over smooth, glazed surface.

Other natural fabrics, such as wool, may also be treated by theabove-described method of my invention, as well as such cellulosicfabrics as cotton, rayon, or the like.

Ripples orwavesmay also be produced in a fabric fabric comprising firsttreating said fabric with a resinous material adapted to be hardened,then supporting said treated fabric on a movable web having acontractible curved fabric-supporting surface cooperating with anopposed fixed curved surface to confine said fabric therebetween, nextprogressively releasing a limited length only of said fabric from saidopposed confining surfaces while contracting said fabric supportingsurface of said web to reduce the surface speed of travel of said weband fabric to wave said fabric supported thereon while said limitedlength of said fabric remains substantially unconfined, and finallyconfining said waved fabric between said contracted fabric-supportingweb surface and an opposed curved surface to at least partially hardensaid resinous material to set said waves to provide a resin treatedwaved fabric resistant to washing.

2. A method of finishing a continuous sheet of textile fabric to providesubstantially parallel and uniform waves therein generally perpendicularto the warp yarns of said fabric comprising first treating said fabricwith a resinous material adapted to be hardened by heating, thensupporting said treated fabric on a movable web having a contractiblecurved fabric-supporting surface cooperating with an opposed fixedcurved surface to confine said fabric therebetween, next progressivelyreleasing a limited length only of said fabric from said opposedconfining surfaces while contracting said fabric-supporting surface ofsaid web to reduce the surface speed of travel of said web and fabric towave said fabric supported theron while said limited length of saidfabric remains substantially unconfined, and finally confining saidwaved fabric between said contracted fabric-supporting web surfacecooperating with heated opposed curved surface to at least partiallyheat harden said resinous material to set said waves to provide a resintreated waved fabric resistant to washing.

3. A method of finishing a continuous sheet of textile fabric to providesubstantially parallel and uniform waves therein generally perpendicularto the warp yarns of said fabric comprising calendering said fabric toprovide a smooth surface thereon, then treating said fabric with aresinous material adapted to be hardened by heating, then supportingsaid treated fabric on a movable web having a contractible curvedfabric-supporting surface cooperating with an opposed fixed curvedsurface to confine said fabric therebetween, next progressively re-References Cited in the file of this patent UNITED STATES PATENTS2,021,975 Wrigley et al Nov. 26, 1935 2,193,340 McConnell Mar. 12, 19402,627,644 Foster Feb. 10, 1953

1. A METHOD OF FINISHING A CONTINUOUS SHEET OF TEXTILE FABRIC TO PROVIDESUBSTANTIALLY PARALLEL AND UNIFORM WAVES THEREIN GENERALLY PERPENDICULARTO THE WARP YARNS OF SAID FABRIC COMPRISING FIRST TREATING SAID FABRICWITH A RESINOUS MATERIAL ADAPTED TO BE HARDENED, THEN SUPPORTING SAIDTREATED FABRIC ON A MOVABLE WEB HAVING A CONTRACTIBLE CURVEDFABRIC-SUPPORTING SURFACE COOPERATING WITH AN OPPOSED FIXED CURVEDSURFACE TO CONFINE SAID FABRIC THEREBETWEEN, NEXT PROGRESSIVELYRELEASING A LIMITED LENGTH ONLY OF SAID FABRIC FROM SAID OPPOSEDCONFINING SURFACES WHILE CONTRACTING SAID FABRIC SUPPORTING SURFACE OFSAID WEB TO REDUCE THE SURFACE SPEED OF TRAVEL OF SAID WEB AND FABRIC TOWAVE SAID FABRIC SUPPORTED THEREON WHILE SAID LIMITED LENTH OF SAIDFABRIC REMAINS SUBSTANTIALLY UNCONFINED, AND FINALLY CONFINING SAIDWAVED FABRIC BETWEEN SAID CONTRACTED FABRIC-SUPPORTING WEB SURFACE ANDAN OPPOSED CURVED SURFACE TO AT LEAST PARTIALLY HARDEN SAID RESINOUSMATERIAL TO SET SAID WAVES TO PROVIDE A RESIN TREATED WAVED FABRICRESISTANT TO WASHING.